Products Architectural Louvers, Dampers, Roof Curbs, Actuators, Grilles, Sunshades and more. Dampers - Round Dampers: Model:R-OB Round Multi-Blade Damper APPLICATION The Model R-OB multi-blade damper was developed to maintain a more even airflow through the duct system. R-OB DOCUMENTS - Submittal Sheet - R-OB BIM (REVIT) - Actuator Sizing Chart UV Products Iris Dampers Drop Plenum Diffusers Balancing / Regulating Dampers Louvers Dampers UL Listed Dampers Roof Curbs and Rails Sunshades Architectural Grilles Ventilators Doors Actuators Fans Air Measuring Products VAV Terminals Security Bars & Grilles Plenums Duct Take-Offs Custom Work Manufacturer Cross Referencing System View Now Previous Next